When I believed I was a genius and that metadata was my intellectual property, I developed a procedure in Firebird to track changes on a single table, something with ids and time stamps. So, I've done a mega clever move and deleted the source of this procedure.
Does anyone knows a BLR decoder, or the docs that I need to build one?
I've seen a BLR display tool (in Jason Wharton's IB admin tool), but it would only display BLR names, not transliterate back to SQL/proc language. I think what you're looking for doesn't exist.
You can get BLR documentation here, though.